Evaporating apparatus



(No Model.) 2 Sheets-Sheet 1.

0. O. PEGK.

EVAPORATING APPARATUS,

No. 426,140. Patented Apr. 22, 1890.

WiT ESSES:

NVENTDN (No Model.) 2 Sheets-Sheet 2.

G. O. PEGK. EVAPORATING APPARATUS.

N0. 426,140. Patented Apr. 22, 1890.

Wirgssss: N N

. VE TEN NITE STATES ATENT OFFICE.

CASSIUS G. PECK, OF NEIV YORK, N. Y.

EVAPORATI NG APPARATUS.

SPECIFICATION forming part of Letters Patent No. 426,140, dated April 22, 1890.

Application filed April 6, 1889.

T0 aZZ whom it may concern:

Be it known that I, CAssIUs (l. PECK, a citizen of the United States, residing in the city, county, and State of New York, have invented certain new and useful Improvements in Evaporating Apparatus, of which the following is a specification.

My invention relates to vacuum evaporating apparatus. It is intended primarily for the evaporation of brine in the manufacture of salt; but it may be advantageously applied to the evaporation of other liquids.

The principal features of the invention. are, first, placing the heating-surface which heats the liquid to be evaporated outside of the vacuum pan or chamber, and by means of a pump causing a rapid circulation of the liquid under treatment between said heatin surface and the vacuumchamber; second, giving the bottom of the vacuum-chamber a hopper or inverted-cone form, in combination with a convcyer communicating with the bottom of the chamber, for the purpose of delivering wherever required outside the chamber the solid material which collects in the bottom; third, in connecting two or more of such chambers together and with a vacuum pump or pumps, to the end that two or more uses of the primary heat may be obtained in evaporatin 111 the drawings, Figure I is a vertical central section through line a: as, Fig. II, of two connected masonry vacuum-chambers set in separate open tanks and provided with exteriorly-placed heating-surface, and also an additional tank for heating the liquid under treatment on its passage to the vacuum-chambers. I i II is a plan view of the same apparatus, showing also the centrifugal pumps used in circulating the liquid under treatment between the vacuum-chambers and the exteriorlydocated heatingsurface, the doubleacting vacuum-pump, and an overflow-tank. Fig. III is a vertical section at right angles to Figs. I and II, showing on a larger scale the interior form of the vacuunr-chamber, and also the arrangement of a conveyor for discharging solid matter deposited from the chamber.

In Fig. I coil-hcaters B B are placed within the tanks I) D. These coil-heaters maybe Serial No. 306,238. (No model.)

of any convenient form or construction to suit the character of the fluid in which they are placed, the essentials being that there shall be sufficient surface to effect the desired amount of evaporation, and that where deposits or incrustations are liable to form the heating-surface shall be so arranged as to be accessible for cleaning.

A circulation of steam or hot liquid through pipe Z) Z) heats coil B and through it the liquid contained in tank D. This liquid is forced into vacuum-chamber A by the vertically-set centrifugal pump E through pipe 6. Vapor given off from the heated liquid and collecting in the top of chamber A is withdrawn by vacuum-pump 0, being mostly condensed in coil B on its passage to the pump. The condensation of vapor in said coil supplies heat to the liquid in tank D, and this liquid is forced into chamber A by the centrifugal pump E. Vapor collecting in the top of chamber A is removed by the vacuumpump C, and is mostly condensed in coil B in tank D on its way to the pump. A constant and rapid circulation of the liquid in tanks D D is maintained between chambers A A and heater-coils B B by pumps E E. The direction of this circulation is shown by arrows. This rapid circulation effects two important results: first, it maintains the liquid inside the vacuum-chambers at approximately the same temperature as that in contact with the heating'coils; and, second, the force of the current flowing out from the vacuum-chambers sweeps down the sloping sides of the chambers and out through circular openings 0. a into the basins or pockets (Z (Z in tanks D D the granular or other solid matters deposited from the liquid through the process of evaporation. The deposited mattcr is thus brought in contact with the conveyors F E, which are driven from any convenient source of power, and which elevate and deliver it outside the tanks. These conveyors may be of any convenient form of construction to suit the material being handled, such as a chain and buckets driven by sprocketwheels or a belt with or without buckets attached, or a screw or worm working in a case.

Pipes 1: b are so connected through coils B B with cylinders c c of pump 0 that each cylinder may be operated as a separate pump, or the suction of both cylinders may be applied to one pipe. Thus in the former case valve 1)? is closed and valves b b are opened,

and in the latter case valve 1) is more or less opened and valves b 11 are more or less closed in proportion to the amount of suction which it is desired to apply to each cylinder.

The liquid to be evaporated is first received and heated in tanks D and then flows successively into tanks D and D, as required for maintaining a suitable supply in said tanks, the supply being preferably arranged as a gravity flow from one tank to the other, although a pump or pumps may be used for delivering the feed-liquid from tank D to tanks D and D. This constitutes a tripleeifect apparatus.

The evaporation in vacuum -chamber A serves to effect the evaporation in chamber A, and heat passing from the latter chamber with the vapor is absorbed by the feed-liquid in tank D The height of vacuum-chambers A A corresponds with the degree of vacuum to be maintained, being also governed by the 11ature of the liquid which is to be treated. Thus when the vacuum carried is high and the liquid has a tendency to foam, chambers or cylinders of thirty feet and upward in height will be required, while with a low degree of vacuum and a liquid from which vapor separates readily, ten to fifteen feet in height will be sufficient.

The vacuum-chambers I preferably @011- struct of some form of masonry, such as hard bricks or stones laid up with hydraulic cement and coated upon one or both surfaces of the walls (inside and out) with said cement, as set forth in my application, Serial No. 323,463, concurrent herewith, said application being a subdivision of the present one.

The tanks D D D D are supposed to be constructed of masonry and lined with Portland cement, but may of course be built of wood or metal, and they may be covered or not, as is most convenient. Tank D is designed for an overflow-tank, so that when the tanks D D D are not made sufficiently large to hold the liquid, in case the vacuum should suddenly fail in chambers A A it may everflow into said tank. Usually, however, the three tanks D D D Will be made of sufficient size as not to overflow, in case of failure of vacuum in chamber A A to the extent of letting the contents of the chambers flow out into said tanks.

The two greatest advantages in placing the heating-surfaces, as in coils B B, Figs. I and II, outside the vacuum-chambers A A, are accessibility for cleaning, so that said surfaces may be cleaned even while the process of evaporation is proceeding, and provision for removal of solid deposits as fast as they accumulate at the bottom of the vacuumchamber. To make such removal as easy as possible, the bottom of the chamber is given the form of a hollow inverted cone, so that the current of liquid constantly flowing out of the chamber may carry with it within reach of the conveyer all solid matter deposited by the process of evaporation within the chamber; but when it is not necessary to provide for such rapid removal by means of a conveyer or when the liquid under treatment simply thickens by concentration, but does not precipitate solid matter, the bottom of the chamber may be made fiat and such number of arched openings provided as will render the interior of the chamber sufficiently ac cessible, the top of the arched openings being of course below the liquid-level in the tanks.

For circulating the liquid between vacuumchambers A A and coils B 13 any suitable form of pump may be employed.

I do not herein claim, broadly, a vacuumchamber in communication with an exterior tank for heating the liquid under atmospheric pressure, as this arrangementis also included in my concurrent application, Serial No. 306,237; but

That I claim as my invention, and desire to secure by Letters Patent, is-

1. In evaporating apparatussubstantially such as described, the combination of a vacuum-chamber, an exterior tank for heatingthe liquid under atmospheric pressure, and apparatus for enforcing a circulation of the heated liquid through and between the said vacuum-chamber and heating-tank, substantially in the manner and for the purpose described.

2. In evaporating apparatus substantially suchas described, the combination of a vacuum-chamber, an exterior tank for heating the liquid under atmospheric pressure, apparatus for enforcing a circulation of heated liquid through and between the said vacuum-chamber and heatin -tank, and an automatic conveyer for removing the solid products of evaporation, substantially in the manner and for the purpose described.

3. In evaporating apparatus substantially such as described, the combination of a vacuuni-chamber formed with converging side Walls which concentrate the solid products of evaporation at the bottom of the chamber, an exterior tank for heating liquid under atmospheric pressure, apparatus for enforcing a circulation of heated liquid through and between the said vacuum-chamber and the exterior heating-tank, and an automatic conveyor for removing the solid products of evaporation from the lower portion of the vacuum=-chamber, substantially in the manner and for the purpose described.

4. In evaporating apparatus substantially such as described, the combination of an exterior tank for heating liquid under atmospheric pressure, a vacuum-chamber situated within and communicating with said exterior tank, a heating-coil situated in said exterior tank, an outer condensing-coil communicat- IIO ing with the vapor-space of the said vacuumchamber, and apparatus for exhausting the vapor from the said vacuum-chamber through the said exterior condensing coil, substantially in the manner and for the purpose described.

5. In evaporating apparatus substantially such as described, the combination of two or more exterior tanks for heating liquid under atmospheric pressure, two or more vacuumchambers, each situated in one of said exterior heating-tanks and communicating therewith, coils situated in the said exterior heating-tanks and each communicating with vacuum-space in the vacuum-chambersituated in the preceding heating-tank, and apparatus for exhausting the vapor from said vacuumchambers through the said exterior coils, by which latter the vapor is condensed and the liquid in the said exterior tanks heated, substantially in the manner and for the purpose described.

6. In evaporating apparatus substantially such as described, the combination of two or more vacuum-chambers, two or more exterior tanks for heating liquid under atmospheric pressure, heating-coils situated in said exterior tanks and communicating with the vapor-spaces of the said vacuum-chambers, and a duplex exhaustpump connected with said heating-coils and provided with valves by which the action of the pump upon the respective coils may be varied, substantially in the manner and for the purpose specified.

CASSIUS C. PEG/K. Witnesses:

L. B. PEOK, W. L. DE GRAW. 

